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A Si-based integrated probe is proposed for cross-sectional velocity distribution measurements. The measuring principle is based on a combination of simultaneous multipoint measurement using spatial encoding and nonmechanical scanning. The scanning function of the probe employing chirped focusing grating couplers in the transmitting optics is simulated.

Here we present an image sensor with a new type of phototransistor that realizes a wide dynamic range for photons. The proposed phototransistor has a new function of dynamic range compression, so that the output signal is not limited by the power supply voltage.

Despite intensive research in the field of applied superconductivity only now we start to use of this phenomenon for the most obvious application, namely, power transmission. At present, it can be seen an explicit shift from AC to DC HTS cable systems due to the many advantages of the DC ones. However, even at constant current transmission line is subjected to current fluctuations and, consequently, AC losses. One more reason for reducing the efficiency of HTS lines is current imbalance. It is associated with the presence of electrical resistance at the soldered connections of the superconducting tapes. Although these resistances are very low, but against the background of zero resistance of the rest of the superconductor they determine the individual currents in tapes and introduce essential nonlinearity into the dependence of these currents on the total current. In order to estimate AC losses the frequency characteristics of the ripple current were calculated taking into account current imbalance in the cable.

In this work, a drop-on-demand piezoelectric ink-jet system has been employed to fabricate disposable photodiodes as the detectors on the integrated lab-on-chip lasers. J-aggregated films of a cyanine dye, doped into a conductive polymer, poly(3,4-ethylenedioxythiophene) poly(styrene sulfonate) (PEDOT:PSS) on the indium tin oxide (ITO) substrate have made by the ink-jet method, respectively. The influence of ink-jet single dot local area and spot thickness by spot stacking on the J-aggregate formation and also the wavelength sensitivity of the photodiodes have been systematically investigated and reported.

In this study, we synthesized the new spirobifluorene derivatives; hexylbiphenyl-spirobifluorene (HBP-Spiro) and demonstrated the operation of a distributed-feedback polymer waveguide blue laser. In addition, we investigated the optical and lasing properties of spirobifluorene derivatives including photostability. The maximum experimental slope efficiency and the energy threshold of a HBP-Spiro-doped waveguide laser were 3.6% and 1.9 uJ, respectively. An operation lifetime of 27,000 shots was obtained for a pump-pulse duration of 1.2 ns and energy of 3.0 uJ at a wavelength of 355 nm.

The tunable waveguide dye laser on the plastic optical fiber (POF) was developed. Narrowband spectrum DFB laser operation of the dye laser pumped from optical coupling between optical fiber to the dye laser can be obtained, and wavelength modification with bending of the fiber can be observed.

Multicolor laser array, a novel type of pumping method, Transversal-Quasi-Mode-Coupring on waveguide laser was demonstrated Four color laser array was demonstrated by experiments.

Spirobifluorene derivative, as novel and high performance organic compound for light emitting diodes, shows laser action in a distributed feedback waveguide cavity. This compound was developed for wet process such as a pritable laser fabrication system. Spirobifluorene-doped distributed feedback solid-state laser shows loger durability than traditional.

Integration techniques of tunable DFB solid-state dye laser on PDMS chip were studied. The fabrication of a micro flowcytometry chip integrated with DFB lasers as a first example was also demonstrated.

Organic photo-diodes based on various J-aggregated cyanine dyes, NK-3989, NK-1952 and NK-2203 doped into conductive polymer films patterned by ink-jet method on ITO substrates have been obtained. Wavelength sensitivity has been observed from the photo-diodes.

As a direct patterning technique for the cost-effective fabrication of organic electronic devices, drop-on-demand ink-jet printing has generated extensive research interests in recent years [1,2]. Compared with other film deposition techniques, ink-jet method is highly preferable due to its versatility, miniaturization and high precision patterning. It is proposed that a kind of photo detector may be available on the integrated lab-on-chip lasers by ink-jet method [3]. And the cyanine dyes may also be the one of the most promising candidates due to their tendencies to form J-aggregates with characteristic sharp, steep and narrow absorption peaks [4].

Solid-state organic waveguide dye lasers having distributed feedback (DFB) grating have several attractive features including minimal cost, easy fabrication, flexibility and compactness. These lasers exhibit several features of the broadband tunability, narrow-band lasing, and low threshold. Second harmonic generation (SHG) of yellow-red light from organic waveguide dye laser can achieve a novel tunable near-ultraviolet laser device based on organic material with the above-mentioned features. However, a conventional waveguide dye laser exhibit extremely low optical-optical efficiency, moreover, low output energy. Therefore, near-ultraviolet laser cannot be effectively generated by using conventional waveguide dye lasers. Development of high-efficiency, high-power organic waveguide laser is necessary to achieve a near-ultraviolet laser based on organic material.

Novel waveguided PPLN-SHG device was demonstrated. Two type of dual-phase modulated PPLN device was fabricated and investigated. Inequilateral-type was similar to previously reported. Equilateral-type was newly proposed and demonstrated for first time.

Integration techniques of tunable film dye lasers on a plastic optical application chip were studied. We fabricated microflowcytometry chip integrated with DFB film lasers as a first example. Preliminary LIF experiment was also demonstrated.

Integration techniques of tunable film dye laser on a plastic optical application chip were studied. We fabricated micro flowcytometry chip integrated with DFB film lasers as a first example, and tried to show its usefulness by preliminary experiment of fluorescence flowcytometry.

Combination of intra-cavity SHG and passively-Q-switching demonstrated on 473 nm quasi-four-level Nd:YAG laser. Periodically-poled MgO:SLT was inserted into the 10 mm length cavity of passively-Q-switched Cr:Nd:YAG laser. A longitudinally pumping with 4 W laser diode shows beam quality of M2 ap1. The output energy of 29 muJ and pulse duration of 3.1 ns were obtained.

We have demonstrated a waveguide dye laser including a thin active random layer. Use of thin film containing nano-size particles as well as laser dye (random active layer) is a promising solution to improve the efficiency. In this paper, we report a full characterization of the device parameters. We also demonstrated a low-threshold, highly efficient distributed feedback dye laser using an active random scattering media. And the slope efficiency of 38.5% and threshold of 0.96 muJ have achieved, respectively. This device has the ability that can be applied for the laser spectroscopy

A novel type of pumping method, Quasi-End-Firing on waveguide laser was analyzed and demonstrated. A numerical simulation predicts controllability of pumping beam coupling. It also confirmed by experiments.

A coupling-control of quasi-end-firing DFB film dye laser on a chip was proposed. The absorption length can be changed by slightly modification of refractive index, and it makes pumping switch possible on the laser array.

Summary form only. Tunable phase conjugation in the visible region has received much attention in several application fields such optical image processing, spectroscopy and medical optics in recent years. In this paper, we present an efficient injection-seeded Rhodamine 6G solid-dye laser cavity, which exhibits phase conjugate energy-extraction of >13,000% in the broad-band from 558 nm to 564 nm.

Summary form only given. Efficient phase conjugation in saturable gain medium solid dye has received much attention in application fields such as optical image processing, spectroscopy, and medical optics. For practical phase conjugators, an energy extraction efficiency, defined as a ratio of the extracted phase-conjugate energy to the total beam energy injected externally into the phase conjugator, is a more important parameter than the phase-conjugate reflectivity. We present an efficient phase conjugator by degenerated four-wave mixing in a laser injection-seeded solid dye laser. Energy extraction efficiency as much as 130 was obtained. The solid laser dye was composed of matrix polymethyl methacrylate with 0.1-0.2 wt.% doping of Rhodamine 6G dye.